Devices for squaring tubular folding box blanks

ABSTRACT

A device is disclosed for squaring flat collapsed tubular folding box blanks disposed upright in a horizontally extending stack in which the endmost blank is retained by lugs overlapping the blank marginally. A suction cup draws the blank out of the grip of retaining elements and drags the lower blank portion over a cam, thus causing the minor panel which is engaged by the cam to assume an angular position to the cup-held major panel. An abutment element is provided above the cam for engaging the upper portion of the withdrawn blank in a position in which the blank has sufficient space behind it to expand. The abutment element also catches second blanks in case of accidental double feeding.

United States Patent 72] lnventor Eugene P. Jaroch Menlo Park, Calif. [21 Appl. No. 784,622 [22] Filed Dec. 18, 1968 [45] Patented Jan. 5, 1971 [731 Assignee Kliklok Corporation New York, NY. a corporation of Delaware [54] DEVICES FOR SQUARING TUBULAR FOLDING BOX BLANKS 5 Claims, 5 Drawing Figs.

[5 2] US, Cl. 93/53 [51] lnttcl B3lb 1/76 [50] Field of Search 93/53, 53PSD, 530R, 53M

[56] References Cited UNITED STATES PATENTS 3,142,232 7/1964 Pierce et a]. 93/53 Primary Examiner-Bernard Stickney Anorney Howard G. Russell ABSTRACT: A device is disclosed for squaring flat collapsed tubular folding box blanks disposed upright in a horizontally.

extending stack in which the endmost blank is retained by lugs overlapping the blank marginally. A suction cup draws the blank out of the grip of retaining elements and drags the lower blank portion over a cam, thus causing the minor panel which is engaged by the cam to assume an angular position to the cup-held major panel. An abutment element is provided above the cam for engaging the upper portion of the withdrawn blank in a position in which the blank has sufficient space behind it to expand. The abutment element also catches second blanks in case of accidental double feeding.

. I I Y 34 ia 1e I PATENTEDJAH 51% 3,552,280

sum 1 [IF 5 INVEN'IOR. E age/1e R Jcz roe/z BY WW ATTORNEY PATENTED JAN 5 l97| SHEET 2 [IF 5 PATENTEDJAN 5mm SHEET 3 OF 5 INVENTOR. Eugene A t /aroc/z l ATTORNEY PATENTEUJAH 5197i s'nmuors h w mm Wm H 6 ATTORNEY PATENTEU JAN 51971 snmsors INVINIOR 21 rze F10 0/2 BY 41/, Arro/viy DEVICES FOR SQUARING TUBULAR FOLDING BOX BLANKS The present invention is directed to the improvement of devices for squaring flat collapsed tubular folding box blanks disposed upright in a horizontally extending stack of blanks, the devices being of the type in which primary lug elements marginally overlap the foremost blank of the stack and in which a vacuum cup mounted for oscillation on an arc about a substantially horizontal axis parallel to the collapsing creases of the blank grasps the forwardly facing major panel of the foremost blank and draws it out of the grip of the primary lug elements. The cup then draws the lower blank portion at, and adjacent to, the lower collapsing crease over a cam, thereby causing the blank to be squared as the panel which is gripped by the vacuum cup approaches a horizontal position.

The squared blank is finally delivered to a suitable conveyor which maintains it squared and moves it past filling and closing stations.

Dilficulties are encountered in the squaring of the blanks if the operation is carried out with great rapidity, a representative rate being 300 blanks per minute. At this rate less than one-fifth of a second is available for the withdrawal of the blank, the squaring operation and the transfer to the conveying device, whereafter the vacuum cup returns to the magazine to grasp the next blank.

The squaring of the blank involves the separation of the major panels, which become the top and the bottom, respectively, of the resulting box and the folding of the minor panels into right angular position to the major panels. This folding operation is performed basically by dragging one of the minor panels over the cam surface. The folding of the other minor panel occurs indirectly by reason of the fact that the tubular blank is a parallelogram in end view.

The folding of the second minor panel is interfered with if the major panel grasped by the vacuum cup is bowed excessively, for example as a result of an uneven flow of air into the space between the rapidly separating major panels which are of considerable size.

Another difficulty is presented by the fact that the blank whose squaring beings with its withdrawal from the retaining lugs cannot square properly until there is sufficient space behind the blank.

A third difficulty is presented by accidental misfeeding of a second blank which may be drawn through the magazine gate together with the first blank, either by failure of the air to enter between the blanks rapidly enough or by interlocking of laterally projecting flaps and panels which form the closure.

The aforementioned problems are remedied by the provision of abutment means which engage the blank adjacent its upper collapsing crease after the upper blank position has escaped the retaining lugs of the magazine gate. The abutment means is located above the cam and is preferably so spaced from the magazine gate that the blank travels less than the 1 dimension of the minor panel and more than half that dimension from the gate before striking the abutment means.

The abutment means performs several functions:

It provides, together with the cam, a restricted escape passage for the withdrawn blank through which the blank can pass can only pass if both the lower minor panel, engaged by the cam and the upper minor panel are folded into angular position with respect to the major panels. The folding of the upper minor panel is assisted by the abutment means, as the latter prevents forward bowing of the cup-held major panel,

devices, the expansion of the blank occurs at a slightly later, but controlled, point of the blank travel.

It is for this reason advantageous to place the abutment means ahead of the foremost blank in the stack by less than the dimension by which the blank expands but more than half that dimension. The dimension referred to is also the height of the minor panel.

The various objects, features and advantages of this invention will appear more fully from the detailed description which follows accompanied by drawings showing, for the purpose of illustration, a preferred embodiment of the invention. The invention also resides in certain new and original features of construction and combination of elements hereinafter set forth and claimed.

Although the characteristic features of this invention which are believed to be novel will be particularly pointed out in the claims appendedhereto, the invention itself, its objects and advantages and the manner in which it may be carried out may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part of it in which:

FIG. 1 is a perspective view of the magazine portion of a blank squaring device containing a single .blank;

FIG. 2 is a perspective view of the upper portion of the magazine gate showing a blank in the process of being squared, the magazine containing a stack of blanks;

FIG. 3 is a perspective downward view showing details of the mechanism in front of the magazine gate, the blank being at an advanced stage of squaring;

FIG. 4 is a perspective view of the mechanism of FIG. 3 showing the blank released at the point of entering a conveying device, and

FIG. 5 is a view similar to FIG. 2 illustrating a condition of accidental misfeeding of blanks.

In the following description and in the claims various details will be identified by specific names for convenience. The names, however, are intended to be generic in their applica tion. Corresponding reference characters refer to corresponding parts in the several figures of the drawings.

The drawings accompanying, and forming part of, this specification disclose certain specific details of construction for the purpose of explanation of broader aspects of the invention, but it should be understood that structural details may be modified in various respects without departure from the principles of the invention and that the invention may be incorporated in other structural forms than shown.

Details of the blank B to be handled by the illustrated device are best seen in FIGS. 1 and 4. The blank comprises two major panels 11 and 12 of a dimension H and two minor panels 13 and 14 of a dimension h, the dimensions H and h being girth dimensions of the blank. In the completed box panels 11 and 12 become the top and the bottom, respectively, and the minor panels 13, 14 are the sides.

The ends of the box are formed by corner flaps l5 articulated to the minor panels and outer and inner end panels l6, 17, respectively, articulated to the major panels.

A glue lap 18 is articulated to one of the major panels 12 and is adhered to the inside surface of the side panel 14, as indicated in FIG. 4. This makes the blank B a tubular structure which is delivered in flat collapsed condition by the blank manufacturer, the collapsing creases being a lower crease 19 and an upper crease 20. The distance between the collapsing creases isH h.

, The box ends may be locked by T-shaped tabs 21 on the outer end panels 16 insertable into slits 22. All of the described blank details are conventional.

The blanks are stored in a magazine in stacked condition as indicated at S in FIG. 2. The magazine is best seen in FIG. 1 and comprises inclined rods 23 and 24 terminating at a magazine gate 25, the gate being essentially a frame carrying retaining element or lugs 26 marginally overlapping the foremost blank to prevent it from falling out of the gate under the pressure of the inclined stack 5 behind it. Additional retaining elements may have the form of a lip 126 at the bottom and semispherical buttons 226 at the top (FIG. 2).

The blanks rest on the rods 23 at their lower collapsing creases and are kept in line by the lateral rods 24.

Only one blank is shown in the magazine in FIG. 1, as a stack of blanks would have obscured the retaining elements 26, 126.

The stack S of blanks in the magazine is subject to pounding by a reciprocating vacuum cup feeder later to be described. In order to prevent blanks from tipping over under such pounding, a rearward catch is provided comprising a bracket 27 carrying a flat blade 28 on the underside which snaps behind the top edge of a certain blank and prevents it, and the blanks in front of it, from tipping over. This construction is basically known and is described in greater detail in US. Pat. No. 3,210,072 ofOct. 5, 1965 to Baker et al.

Turning to FIG. 4, a pair of vacuum cups 29 are mounted on the end of an arm 30 fixed on a transverse oscillating shaft 31 parallel to the collapsing crease 19 of the blank. The oscillating shaft 31 moves the cups 29 on anarc about the shaft axis, the lower end position being the one shown in FIG. 4, the upper end position being one in which the cups contact the panel 12 of the foremost blank of the stack. A pointed element 32, best seen in FIG. 3, digs slightly into the panel 12 and prevents it from slipping relatively to the cups.

The arm 30 of the vacuum cups 29 is flanked by a pair of earns 33 over which the panel 14 is dragged after removal ofa blank by the cups (see FIG. 3).

The cups 29, which are connected to a valve-controlled vacuum line in a known manner, attach themselves to the foremost blank in the magazine and pull it out of the grip of the marginal retaining elements 26, 126, 226. Shortly thereafter the lower collapsing crease 19 of the blank strikes the cams and is progressively forced upwardly until the surface of the panel 14'comes to rest on the cam surfaces and is folded into angular position with respect to the panel 12 (FIG. 3.).

As the blank has the form of a parallelogram in side view (FIGS. 2 and 3) the upper minor panel 13 is also moved towards an angular position with respect to the panel 12. The panels 11 and 12 separate as the blank is being squared.

The dragging of the blank generally causes considerable flexing of the major panel 12, as a result of which the folding of the upper minor panel 13 is not always certain and sufficient.

In order to prevent failure, and in order to make the squaring operation positive, a secondary lug or abutment means is provided forwardly of the magazine gate above the earns 30.

As best seen in FIG. 2, a bracket 34 is attached to the upper portion of the magazine frame 25 and carries a transverse bar 35 on its underside. The bar 35 represents a secondary abutment meansor obstruction which is in the way of the upper collapsing crease and strikes the panel 12. adjacent the crease 20.

The distance between the bar 35 and the cam surfaces 33 is such that a nonexpanded blank of the dimension H h cannot clear it, but that an expanded blank of the dimension H or slightly more than H can pass through the restricted passage between bar and cams.

The major portion of the squaring operation of the blank occurs when the blank is in contact with the bar 35 at which point there is sufficient space between the panel 12 and the next blank in the magazine to permit the grasped blank to expand, i.e., the panel 11 to move rearwardly with respect to This is a consequence of the relatively slow flow of air into the initially narrow gap between the panels. A blank withdrawn from the magazine may therefore move as far as the bar 35 in unexpanded condition until the bar forces the panels 11 and 12 to separate.

A similar suction effect exists between individual blanks and may occasionally cause a second blank to be drawn out of the magazine. This condition is shown in FIG. 5.

The blank 8, is grasped by, and is under the control of, the vacuum cups but a second blank B was accidentally withdrawn by suction between, or cohesion of, the blanks.

The blank B would normally cause jamming of the machinery into which the squared blanks are delivered. Theabutment element 35 catches accidentally withdrawn blanks and thus renders such instances of double feeding harmless.

The blank B comes to rest on the cams 33 at the bottom at the abutment element 35 at the top and remains arrested until the returning vacuum cups 29 pick it up. It will be remembered in this connection that the spacing of the bar 35 with respect to the earns 29 is less than H h and is therefore insuffi cient to permit theflat blank B to pass.

The squared blank (FIG. 3) is moved into a substantially horizontal position by the vacuum cups 29 and comes to rest on rails 36 of a conveyor whose chains 37 and lugs 38 remove it in a direction towards the observer.

As the blank assumesa horizontal position the vacuum at the cup 29 is relieved in the usual manner to release the blank.

Pushers 39 then move forward and push the squared blank into a conveyor pocket, a pocket being defined betweentwo successive lugs 38 of the conveyor chain.

In the position shown in FIG. 4 the pushers 39 are nearly fully extended and are about to be retracted. Conveyor lugs 38 are seen to rise behind the pushers to advance the squared blank. The conveyor 37, 38 then transports the squared blank to filling and closing stations in a known manner.

1. In a device for squaring flat collapsed tubular blanks disposed upright in a horizontally extending stack of blanks, the device comprising primary lug elements marginally overlapping the foremost blank for retention of the blank at the end of the stack in a position in which the upper and the lower crease along which the blank is collapsed are substantially horizontal, a vacuum cup mounted for oscillation on an are about a substantially horizontal axis parallel to said lower collapsing crease to grasp the forwardly facing panel of the foremost blank and draw the. blank out of the grip of said primary lug elements, and a cam in advance of said lug elements over which cam said cup draws the lower collapsing crease thereby causing the blank to be squared as the said panel approaches a horizontal position, the improvement which comprises secondary lug means above said cam for engaging the blank adjacent its upper collapsing crease after the upper blank portion has escaped said primary lug elements, said cam and said secondary lug element engaging diagonally opposed portions of the parallelogram which the blank presents in side view.

2. A device according to claim 1 in which the secondary lug element is spaced from the plane of the foremost blank held by said primary lug elements by less than the expansion of the blank and more than one-half that distance. I

3. A device according to claim 1 in which the secondary lug element is a bar.

4. In a device for squaring tubular folding box blanks in which a suction cup movable on an arc of substantially about a substantially horizontal oscillating axis grasps the forwardly facing panel of the foremost blank of a substantially horizontal stack of blanks resting upright on the lower of the two creases along which the blanks are collapsed and draws the said foremost blank out of the grip of primary retaining elements which marginally overlap and normally retain the blank in an upright position and thereafter draws the said lower crease of the blank over a cam causing the blank to square, whereafter the squared blank is released by said cup with the said facing panel in a substantially horizontal posi-.

tion, the improvement which comprises a secondary abutment means forward of said primary abutment means in a position to engage the blank adjacent its upper collapsing crease after the upper portion of the blank is drawn by said cup out of said primary retaining'elements.

5. In a device for squaring tubular folding box blanks in which a suction cup movable on an arc of substantially 90 about a substantially horizontal oscillating axis grasps the forwardly facing panel of the foremost blank of a substantially horizontal stack of blanks resting upright on the lower of the two creases along which the blanks are collapsed and draws the said foremost blank out of the grip of primary retaining elements which marginally overlap and normally retain the blank in an upright position and thereafter draws the said lower crease of the blank over a cam causing the blank to square, whereafter the squared blank is released by said cup with the said facing panel in a substantially horizontal position, the improvement which comprises a secondary abutment means forward of said primary abutment means above said cam at a distance from said earn less than the vertical dimension of the collapsed blank and more than the vertical dimension of the major panel of the blank, and at a distance from the foremost blank of the stack less than the dimension of the minor panel and more than one-half the dimension of the minor panel to engage the blank adjacent its upper collapsing crease after the upper portion of the blank is drawn by said cup out of said primary retaining elements. 

1. In a device for squaring flat collapsed tubular blanks disposed upright in a horizontally extending stack of blanks, the device comprising primary lug elements marginally overlapping the foremost blank for retention of the blank at the end of the stack in a position in which the upper and the lower crease along which the blank is collapsed are substantially horizontal, a vacuum cup mounted for oscillation on an arc about a substantially horizontal axis parallel to said lower collapsing crease to grasp the forwardly facing panel of the foremost blank and draw the blank out of the grip of said primary lug elements, and a cam in advance of said lug elements over which cam said cup draws the lower collapsing crease thereby causing the blank to be squared as the said panel approaches a horizontal position, the improvement which comprises secondary lug means above said cam for engaging the blank adjacent its upper collapsing crease after the upper blank portion has escaped said primary lug elements, said cam and said secondary lug element engaging diagonally opposed portions of the parallelogram which the blank presents in side view.
 2. A device according to claim 1 in which the secondary lug element is spaced from the plane of the foremost blank held by said primary lug elements by less than the expansion of the blank and more than one-half that distance.
 3. A device according to claim 1 in which the secondary lug element is a bar.
 4. In a device for squaring tubular folding box blanks in which a suction cup movable on an arc of substantially 90* about a substantially horizontal oscillating axis grasps the forwardly facing panel of the foremost blank of a substantially horizontal stack of blanks resting upright on the lower of the two creases along which the blanks are collapsed and draws the said foremost blank out of the grip of primary retaining elements which marginally overlap and normally retain the blank in an upright position and thereafter draws the said lower crease of the blank over a cam causing the blank to square, whereafter the squared blank is released by said cup with the said facing panel in a substantially horizontal position, the improvement which comprises a secondary abutment means forward of said primary abutment means in a position to engage the blank adjacent its upper collapsing crease after the upper portion of the blank is drawn by said cup out of said primary retaining elements.
 5. In a device for squaring tubular folding box blanks in which a suction cup movable on an arc of substantially 90* about a substantially horizontal oscillating axis grasps the forwardly facing panel of the foremost blank of a substantially horizontal stack of blanks resting upright on the lower of the two creases along which the blanks are collapsed and draws the said foremost blank out of the grip of primary retaining elements which marginally overlap and normally retain the blank in an upright position and thereafter draws the said lower crease of the blank over a cam causing the blank to square, whereafter the squared blank is released by said cup with the said facing panel in a substantially horizontal position, the improvement which comprises a secondary abutment means forward of said primary abutment means above said cam at a distance from said cam less than the vertical dimension of the collapsed blank and more than the vertical dimension of the major panel of the blank, and at a distance from the foremost blank of the stack less than the dimension of the minor panel and more than one-half the dimension of the minor panel to engage the blank adjacent its upper collapsing crease after the upper portion of the blank is drawn by said cup out of said primary retaining elements. 